[ntp:questions] WARNING: someone's faking a leap second tonight

Harlan Stenn stenn at ntp.org
Sat Aug 4 10:10:15 UTC 2012

David Woolley writes:
> Harlan Stenn wrote:
> >> Oh, my mistake:  I quote RFC5905 below, which is for NTPv4, which is 
> >> technically in _draft_ status - though it does seem pretty far along and 
> >> I believe current ntpd adheres to NTPv4, not v3.
> > 
> > The NTP code *defines* the spec, and there will be times when the
> I think you mean the "ntpd reference implementation", e.g. Microsoft's 
> NTP code does not define the standard.

Yes, thanks...

> Also, I don't think this is the correct relationship between RFCs and 
> reference implementations.  An RFC specifies the protocol for a specific 
> reference implementation.  If you do more than fix bugs in the reference 
> implementation, you need a new RFC before it becomes the standard.

Yes, and what you describe is the ordinary case.

The reference implementation for NTP is a bit different - any difference
between the specification and the reference implementation is grounds
for careful scrutiny and deliberation.  Sometimes the spec is correct.
More often than not, the code is the preferred way to go.

There comes a time when ntp-stable is the "current" RFC code and
specification, and ntp-dev is what we use to start to drive the "next"
version of the RFC.  Sometimes there are several releases of the -stable

The push towards an NTP4 RFC began in late '96, with ntp-4.0 being
released in September of '97.  The last release in the 4.0 branch was in
January of '00.  The 4.1 branch (improvements to the V4 spec, etc.) ran
from August of '01 thru July of '03.  The 4.2 branch has run from
October of '03 until now.  We're expecting the last release of the 4.2
branch this summer, and after that we'll start on the next branch of the
code (which is still expected to drive the NTPv4 specification forward).


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